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Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
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CHAPTER FOUR
Geoengineering for Earth Systems and Sustainability

Previous chapters looked at the traditional roles for geoengineering and suggested how they could be affected by new tools and technologies. This chapter looks beyond the traditional roles for geoengineers and projects how they might respond to the new compelling imperatives the world faces. It examines the relationships between geoengineering and sustainability and Earth Systems Engineering (ESE) and then describes how a new Geoengineering for Earth Systems (GES) initiative might be structured in response to these imperatives. There is a compelling leadership role for geoengineers in addressing these new problems, given that the focus of these problems is the health of Earth and that engineering in, on, and with Earth is what geoengineers do.

4.1 SUSTAINABLE DEVELOPMENT

The latter part of the twentieth century was marked by increasing attention to sustainability (i.e., to the question of whether our society can maintain the current quality of life we enjoy in developed countries while raising the quality of life in developing countries). A variety of definitions have been proposed for sustainability and sustainable development. For the purpose of this report, the committee has adopted the definition of sustainable development put forth by the American Society of Civil Engineers (ASCE) and presented in Sidebar 1.1.

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
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An increasing focus on sustainable development is one of the major changes in the practice of civil engineering since the 1989 report. Sustainable development has become generally recognized as an important consideration in civil engineering practice (see Sidebar 1.1). ASCE, in Policy Statement 418, states that “the demand on natural resources is fast exceeding supply in the developed and developing world. Environmental, economic, social and technological development must be seen as interdependent and complementary concepts, where economic competitiveness and ecological sustainability are complementary aspects of the common goal of improving the quality of life.” (ASCE, 2004a). In short, the civil and environmental engineering profession in the twenty-first century faces a new imperative that can no longer be ignored: the incorporation of social issues in addition to the environmental and economic dimensions when developing engineering solutions to societal needs. The simultaneous optimization of these three objectives has been called the triple bottom line of sustainable development.

Research in the discipline of geoengineering has already begun to broaden from its traditional emphasis on the highly focused science of the specifics of soil and rock mechanics in response to this new imperative of sustainable development. Now we are concerned with the life cycles of the materials we use, the long-term environmental effects of our choice of energy supply, and the availability of potable water. Importantly, these issues are considered not just at local or regional scales but at global scales. As noted at the National Academy of Engineering symposium on ESE, Norman Neureiter, former science and technology adviser to the U.S. Secretary of State, said in his remarks titled “It’s the World, Stupid!” (NAE, 2002), “The problems we face—climate change, disaster mitigation, the spread of infectious diseases, safe drinking water, food security, the dramatic loss of species, protection of critical infrastructure, terrorism, proliferation of weapons of mass destruction—do not stop at anyone’s border.” One important implication of this global focus is that we must be concerned not only with advanced technology but also with appropriate technology (e.g., identifying the most appropriate solid-waste management technologies for developing countries where construction of

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×

advanced geosynthetic liner systems may not be feasible and may also not be warranted by the waste stream).

Many of the concerns associated with the sustainable development are directly related to geoengineering, including problems related to environmental health, resource conservation and availability, safe disposal of chemical and nuclear wastes (see Sidebar 4.1), clean up of contaminated sites, sequestration of CO2 to mitigate climate change, and the natural resource needs of the developing world. The developing world is projected to be the source of most of the population growth in the next half-century and this growth is expected to occur almost exclusively in megacities. Basic needs in these megacities—such as water, energy, and sanitation—will be among the most pressing requirements. Therefore, geoengineering will play an important role in the movement toward sustainable development in the twenty-first century (see Sidebar 4.2).

Effective waste disposal and reuse or recycling of the components of obsolete engineered structures are increasing challenges requiring consideration of the full life cycle of facility construction. Solutions to these needs in developing countries should be low in cost to be realistic, and they might well be labor intensive, but they will not necessarily be low tech. Geoengineering for sustainable development must therefore be concerned with reducing the environmental impact of both existing and new facilities and operations in the engineered environment in the developing world.

Sustainable development and concern with the triple bottom line are also becoming important considerations in mining and mineral resource development. In an important two-year study commissioned by the World Business Council for Sustainable Development, the International Institute for Environment and Development (IIED) examined the role of the mining and mineral resources industry in global sustainable development (see Sidebar 4.3). Geoengineering will play an important role in addressing the many challenges identified in this study, including the control, use, and management of land and the impact of mining and mineral recovery on the environment and local communities.

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
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SIDEBAR 4.1
Nuclear Waste Storage—A Cautionary Tale

Nuclear waste storage is an example of a problem with interdependent political, social, economic, and technical aspects. In this country, as in nearly every country facing the need to store spent fuel from reactors, the solution of choice is geologic storage. Geologic storage is not, however, just a geotechnical problem. The choices must be technically sound, but the way that we reach a decision about what to do is governed by national legislation (Nuclear Waste Policy Act and amendments) and affected by social acceptance. The cost is borne by utilities that pay one mil per kilowatt hour into the Nuclear Waste Fund. The current venue for high-level nuclear waste storage in this country is Yucca Mountain in Nevada. However, this project faces delays and legal obstacles promoted by the state government and the Nevada delegation to the U.S. Congress. A lack of consensus on the concept of the project has led to a lack of agreement about the technical and legal approach.

The reasons for these difficulties can probably be traced to the Nuclear Waste Policy Act and its amendments. The original act lays out a process for down-selecting from eight pre-chosen sites, then to five, then to three, and then one based on technical merit. The amendments override the last down-select process and anoint Yucca Mountain as the one and only site. This process created an environment and project culture, including the Yucca Mountain Project, where each of the Yucca Mountain site contractors tried to show their site was appropriate; in other words, they did not try to find out what might be wrong with the site. The amendments were viewed by the state of Nevada as 49 states ganging up on one, and the sense of unfairness that evolved has dominated the state’s response ever since.

Some of the original ideas about why Yucca Mountain might be a good site turned out to be technically complicated. Yucca Mountain was thought to be quite dry and thus waste would not contact water, which could dissolve and transport it. Yucca Mountain is the only repository in the world being considered above the water table. It turns out that the predicted behavior of the hydrologic system over the lifetime of a heat-producing repository in fractured rock that is variably saturated with water is extremely difficult to validate. The above-the-water-table environment is oxidizing and the spent fuel is much more soluble in an oxidized state.

A legal challenge from Nevada has now resulted in the courts vacating the standard that is to be used for licensing the facility. A new standard must be developed that goes beyond a 10,000-year performance period and sets limits on the maximum risk whenever it occurs, a time period expected to be on the order of hundreds of thousands of years. The project continues to have budget problems with vastly different amounts proposed by the administration, the U.S. Senate, and the U.S. House. Utilities see the lack of progress as a major obstacle to the pursuit of future nuclear power. The future of this project is not clear.

Both the United Kingdom and Canada have faced similar obstacles to their nuclear waste programs for similar reasons. However, some countries have done a better job at integrating social, economic, and political concerns on this issue. Perhaps the exemplar is Finland, where an extensive process was used to obtain public agreement about the goals of the nuclear waste program and the need for storing waste in a geologic repository. Once this was accomplished, a plan to choose a site based on predefined technical criteria and local acceptance was developed and executed. Sites were eliminated that did not meet the criteria. The local community of the final site was engaged to develop a clear package of benefits. The program is progressing smoothly and may well be the first high-level waste repository to be commissioned.

SOURCE: Long and Ewing (2004).

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
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SIDEBAR 4.2
Engineering for the Developing World—Challenges and Opportunities

The Challenge

With a current population of 6 billion people, the world is becoming a place in which human populations are more crowded, consuming, polluting, connected, and in many ways less diverse than at any time in history. One may question whether it is possible to satisfy the needs of a growing population and the needs of developing countries while preserving the carrying capacity of our ecosystems, biological diversity, and cultural diversity.

In the next two decades, almost 2 billion additional people are expected to populate Earth, 95 percent of them in developing countries. This growth will create unprecedented demands for energy, food, land, water, transportation, materials, waste disposal, earth moving, healthcare, environmental cleanup, telecommunication, and infrastructure. Engineers will be critical in fulfilling those demands since most of the growth will take place in large urban areas of the developing world. Today it is estimated that up to 2 billion people live in some type of city slum, and the urban share of the world’s extreme poverty is about 25 percent. If engineers are not ready to fulfill the demands of the developing world, who will?

It can take as much as 10 years for a new U.S. engineering graduate to become an engineering manager. Therefore, current graduates will be called upon to make decisions in a sociogeopolitical environment quite different from that of today. In addition to having strong technical skills, tomorrow’s engineers will need to be facilitators of sustainable development, reconstruction, and of social, cultural, and economic changes.

The engineering profession must begin preparing younger engineers to address the needs of the most destitute people on our planet. Problems include water provisioning and purification, sanitation, power production, shelter, site planning, infrastructure, food production and distribution, and communication, among many others. An estimated 20 percent of the world’s population lacks clean water, 40 percent lacks adequate sanitation, and 20 percent lacks adequate housing.

It is clear that there is a demand for educating a new generation of engineers who can better meet the challenges and needs of the developing world. The challenge is to educate engineers who (1) have the skills and tools appropriate to address the issues that our planet is facing today and is likely to face in the next 20 years; (2) are aware of the needs of the developing world; and (3) can contribute to the relief of the endemic problems afflicting developing communities worldwide.

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
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Meeting the Challenge

Since 2001, Engineers Without Borders–USA (EWB-USA) has been working toward meeting the aforementioned challenges. EWB-USA is dedicated to helping disadvantaged communities improve their quality of life by implementing environmentally and economically sustainable engineering projects, while developing internationally responsible engineering students. Projects are initiated by, and completed with, contributions from the host communities, which are then trained to operate the implemented engineering solutions without external assistance.

All EWB-USA projects are carried out by groups of engineering students under the supervision of professional engineers and faculty. The students select a project and go through all phases of conceptual design, analysis, and construction during the school year; implementation is done during academic breaks and summer months. By involving students in all steps of the projects and through experiential learning, students become more aware of the social, economic, environmental, political, ethical, and cultural impacts of engineering projects.

Currently, EWB-USA has about 50 engineering projects in 22 countries. In 2003 alone, more than 50 students from various U.S. schools and 20 professionals were involved in projects in Mali, Mauritania, Senegal, Thailand, Haiti, Belize, Nicaragua, Afghanistan, and Peru. Project description reports can be found at http://www.ewb-usa.org (project pages). All projects are reviewed for quality control by teams of professional engineers before being accepted. EWB-USA has 1,000 members with 69 percent from academia (students and faculty) and 31 percent from practice. EWB-USA is also developing strong collaboration with engineering societies and organizations such as the American Society of Civil Engineers, American Society of Mechanical Engineers, National Society of Professional Engineers, World Federation of Engineering Organizations, and the Association of Soil and Foundation Engineers (ASFE).

Clearly, engineers have a collective responsibility to work toward meeting the Millennium Development Goals set by the United Nations General Assembly (UN, 2000). Appropriate and sustainable solutions are needed to meet the basic needs of all humans for water, sanitation, food, health, and energy while protecting cultural and natural diversity. Improving the lives of the 5 billion poor people whose main concern is staying alive each day is no longer an option for the engineering profession; it is an obligation.

EWB-USA and its partner organizations present many opportunities for professional engineers to become intimately involved in engineering education through projects in developing communities around the world (including the United States). It provides an innovative way to educate young engineers interested in addressing more specifically the problems faced by developing countries and communities.

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×

SIDEBAR 4.3
Breaking New Ground: Mining, Minerals, and Sustainable Development

A two-year project undertaken by the International Institute for Environment and Development (IIED) and commissioned by the World Business Council for Sustainable Development (WBCSD), Breaking New Ground: Mining, Minerals, and Sustainable Development, sought to identify the challenges faced by the mining and minerals sector in contributing to global sustainable development. It lays out a vision for the sector to provide mineral services that will leave a community better off than when a mining project began.

Breaking New Ground begins with the idea that simply meeting market demand for mining and minerals is not a sufficient goal for the industry; it should instead strive to maximize its contribution to sustainable development to the benefit of both the industry and the global community. At the outset the report notes that the mining and minerals industry has one of the worst reputations of any industrial sector, especially in terms of environmental impact and human and local community rights, and “is seen as failing in its obligations and is increasingly unwelcome.”

Starting in April 2000, IIED project teams in London, in concert with teams in the four key regions of southern Africa, South America, Australia, and North America, worked to meet four broad objectives:

  1. To assess the global mining and minerals sector in terms of the transition to sustainable development;

  2. To identify how the services provided through the minerals supply chain can be delivered in ways that support sustainable development;

  3. To propose key elements for improving the minerals system; and

  4. To build platforms of analysis and engagement for ongoing communication and networking among all stakeholders in the sector.

The Mining, Minerals, and Sustainability Project (MMSD) defines the goal of sustainable development as “integrating economic activity with environmental integrity, social concerns, and effective governance systems.” The two-year research and consultation projects of MMSD identified a collection of challenges to sustainable development that the minerals sector faces that include viability of the minerals industry; control, use, and management of land; mining, minerals, and the environment; and local communities and mines.

The report outlines four major categories of actions that can be taken to integrate many of its suggestions on how to support sustainable development in the minerals sector:

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
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  1. Increase understanding of sustainable development;

  2. Create organizational-level policies and management systems for implementing the principles of sustainable development;

  3. Collaborate with others with common interests to take joint steps toward sustainable development; and

  4. Increase our ability to work toward sustainable development at the local, national, and global levels.

Groups affected by initiatives of integrating mining and sustainable development include policy makers, business leaders, public interest campaigners, people working in mines, local communities, and consumers. Breaking New Ground stresses that implementing sustainable development solutions can help reverse the minerals industry’s checkered legacy, which will enable the industry to move forward with greater trust from the communities in which it operates. All parties, from consumers to business leaders, will benefit socially and economically. In addition to addressing a negative legacy, the report calls for other specific actions, including:

  • An industry protocol for sustainable development;

  • Supporting the legalization of artisanal and small-scale mining;

  • Integrated management of the full minerals chain (exploration, extraction, smelting, refining, fabricating, manufacturing, use, reuse, recycling, and disposal, where applicable);

  • More effective government management of minerals investment; and

  • A more equitable international trade regime for minerals.

As a result of the North American Regional Process of MMSD, an approach was developed to test the sustainability of the contributions of mining and minerals activities (IISD, 2002a). A multi-stakeholder work group was asked to

“collaboratively develop a set of practical principles, criteria, and indicators that can be used to guide or test the design, operation, and monitoring of performance of individual, existing or proposed, operations in terms of their compatibility with concepts of sustainability” (IISD, 2002b).

The seven questions that were formulated have much wider applications than just mining and minerals activities. They can also be applied to all development projects that have local and regional social, environmental, and economic impacts. From the seven questions comes a hierarchy of objectives, indicators, and metrics. Simulta

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×

neously, the starting point for assessing the degree of progress is provided by an “ideal answer” to the initial question. The seven questions are:

  1. Engagement. Are engagement processes in place and working effectively?

  2. People (Human Well-being). Will people’s well-being be maintained or improved during and after the project or operation?

  3. Environment (Ecological Well-being). Will the integrity of the environment be maintained or improved as a result of the project or operation?

  4. Economy (Market Economy). Is the economic viability of the company assured; is the community and regional economy better off not only during operation but also postclosure?

  5. Traditional and Nonmarket Activities (Nonmarket Economy). Is the viability of traditional and nonmarket activities in the community and surrounding area maintained or improved with the project or operation?

  6. Institutional Arrangements and Governance. Are the rules, incentives, and capacities in place now and as long as required to address project or operational consequences?

  7. Synthesis and Continuous Learning (Continuous Learning and Adaptive Management). Does a synthesis show the project to be net positive or negative for people and ecosystems? Is a system in place to repeat the assessment from time to time?

MMSD presented Breaking New Ground at the World Summit on Sustainable Development in Johannesburg, South Africa, at an interactive information session in August 2002. MMSD has also published four project follow-up reports that synthesize the results of their commissioned research:

  1. Finding the Way Forward: How could voluntary action move mining towards sustainable development? (2002)

  2. Artisanal and Small-Scale Mining: Challenges and opportunities (2003)

  3. Room to Manoeuvre? Mining, biodiversity and protected areas (2003)

  4. Finding Common Ground: Indigenous people and their association with the mining sector (2003)

Breaking New Ground and the other outputs of the MMSD project can be viewed at http://www.iied.org/mmsd/.

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×

4.2 EARTH SYSTEMS ENGINEERING

We are increasingly aware that we are living in a tightly integrated Earth system where anthropogenic activities have a noticeable, and even dominant, effect on the planet. Accumulations of local activities have an effect on the large-scale behavior, and there are no isolated activities. The recognition of the importance of these phenomena has led the Earth science community to identify a new discipline: Earth Systems Science (ESS). ESS links the biosphere (all life on Earth), geosphere (the rocks, soil, water, and atmosphere of Earth), and anthrosphere (political, economic, and social systems) in order to understand and predict the behavior of Earth systems. From the engineering perspective, each design decision may have systems consequences in other parts of the world, and sometimes these consequences are large, sudden, and unanticipated. Geoengineers need to understand and appreciate the natural interrelationships that tie Earth systems together, and the feedback that is inherent in these systems. As Sarewitz (NAE, 2002) points out, it is a mistake to consider these problems only as scientific issues in which action depends only on gaining fundamental knowledge. Rather, as Sarewitz continues, owing to their global importance we would do better to consider these issues as engineering challenges.

The increasing importance of sustainable development, including the growing recognition that the quality of our engineering directly affects the quality of society and the lives of future generations—combined with the recognition that many engineering decisions cannot (or at least should not) be made independent of the context of the surrounding social systems—has lead to the emergence of ESE as a corollary to ESS. ESE was described by William A. Wulf, president of the National Academy of Engineering (NAE, 2002), as “an emerging multidisciplinary area based upon a holistic view of the interactions between natural and human systems. ESE addresses global, complex, multiscale, multicycle phenomenon, such as climate change, as well as problems of global importance such as urban design.” ESE is the tool, or collection of tools, for helping to achieve sustainable development on regional and global

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×

scales, and geoengineering is an essential component of ESE. Sustainable development is the engineering objective driving the development of ESE. Whereas ESS seeks to understand and predict, ESE seeks to understand and manage Earth systems problems.

Every year, the National Academy of Engineering hosts a public symposium at its annual meeting on a topic it considers crucial to the national welfare. ESE was chosen as the topic for the 2000 symposium in recognition of its importance. John Gibbons, chair of the NAE Technical Symposium on Earth Systems Engineering in 2000 (NAE, 2002), states that “the goals of ESE are to understand the complex interactions among natural and human systems, to predict and monitor more accurately the impacts of engineered systems, and to optimize these systems to provide maximum benefits for people and for the planet.” Because of its focus on the behavior of natural systems (and the impact of human activities on these systems), geoengineering plays an important role in the development of ESE. In fact, with training in both geological science and engineering mechanics and with a civil engineering sensitivity and responsiveness to the needs and demands of society, geoengineers are well positioned to take a lead role in developing ESE.

Geoengineering roles in infrastructure development and rehabilitation, environmental remediation and waste management, and natural resource development are all essential to the development of ESE. However, traditional geotechnical engineering generally considers only the relatively local direct engineering impacts of these activities. ESE demands consideration of the impact of these activities not only on a local scale but also on regional and global scales, as well as in terms of both direct engineering consequences and indirect social and socioeconomic consequences.

Speaking of ESE, Gibbons notes that “many of the science, engineering, and ethical tools we need to meet this enormous challenge have yet to be developed.” While many tools are available for the assessment of the response of individual Earth systems on local scales, there is still a critical need for development of new and improved models for the physical behavior of Earth systems components. Basic research is needed at the level of individual soil particle interactions (e.g., research on the

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×

erodability of soils). On regional and global scales, assessment of impacts will require application of advanced technologies in sensing, systems modeling, and information technology (e.g., satellite-based remote sensing, three-dimensional relational data models). Corresponding advances will be required in the understanding of our social (human) systems and their interactions with natural systems. Furthermore, the uncertainties associated with predicting the regional and global impacts of technologies mandate application of adaptive management techniques (i.e., the observational method) in ESE (see Sidebar 4.4). No other discipline is better positioned than geoengineering to undertake many of the engineering challenges of ESE.

4.3 GEOENGINEERING FOR EARTH SYSTEMS

We agree with the importance attached to ESE by the NAE and see the emergence of a new metadiscipline of GES as a subset of ESE. We define GES broadly as the integration of all disciplines related to geoengineering for earth systems, at all scales. Our definition therefore includes (1) microscale phenomena that affect bonding, conduction phenomena, and other particle-level interactions; (2) the midscale behavior of particle assemblages, including shear strength, dispersion of contaminants in Earth materials, erodability, and hydraulic conductivity; (3) macroscale behavior, such as slope stability and surface water infiltration; (4) megascale phenomena such as regional sediment transport and groundwater aquifer recharge; and (5) engineering required for mitigation on global climate change.

GES encompasses all of the seven areas where geotechnology contribute to national needs identified in Chapter 2: (1) Waste management (and environmental protection); (2) infrastructure development and rehabilitation ; (3) construction efficiency and innovation; (4) national security; (5) resource discovery and recovery; (6) mitigation of natural hazards; and (7) frontier development and exploration. However, by definition and by necessity the GES perspective on these issues is a global systems perspective.

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×

SIDEBAR 4.4
The Observational Method and Adaptive Management

The observational method describes a risk-based approach to geoengineering that employs adaptive management, including advanced monitoring and measurement techniques, to substantially reduce costs while protecting capital investment, human health, and the environment. Development of the observational method in geoengineering is generally attributed to Terzaghi (Casagrande, 1965; Peck, 1969). The method consists of the following steps (Peck, 1969):

  • Assess probable and adverse outcomes;

  • Establish key parameters for observation;

  • Calculate observational parameters under probable and adverse conditions;

  • Measure observational parameters and compare to calculations;

  • Compare predicted and measured parameters; and

  • Change the design as needed.

The observational method has several caveats. One must be able to define an action plan for every conceivable adverse condition. The method cannot be used if you cannot develop a predictive model for the behavior (i.e., you must have a model that can calculate the parameters you will subsequently observe). You must be able to monitor the parameters you can predict. This is not a trivial problem as often we can measure what we cannot calculate and vice versa. This means that the monitoring plan must be chosen very carefully with a good understanding of the significance to the problem. Mistaken preconceptions about the dominant phenomena that control system behavior can lead to choosing irrelevant observational parameters and cause the method to fail.

Casagrande (1965) described limitations to the use of the observational method in his classic geotechnical paper on “The Role of the Calculated Risk in Earthwork Engineering.” Casagrande postulated that risks inherent to geotechnical practice include engineering risks and human risks, calculated risks and unknown risks, and voluntary risks and involuntary risks. Calculated risks are risks based on uncertainties associated with engineering analyses of known phenomena. Casagrande called for the use of the observational approach (i.e., an adaptive management method employing instrumentation and monitoring) to manage calculated risks.

The observational approach is also embodied in what is sometimes referred to as “adaptive management,” or “staging,” approaches to complex engineering problems. Like the observational method, adaptive management is designed to be used on problems where it is not possible to definitively predict the outcome of engineering choices because the system is too complex, the processes are not well enough designed, or the systems cannot be characterized adequately. The use of adaptive management to deal with a seemingly intractable geoenvironmental problem is discussed with respect to the Yucca Mountain Project in the NRC report One Step at a Time (NRC, 2003c). The method is most applicable when the project is one of a kind, the methods and the outcomes are controversial, and the consequences of the project will take a long time to evolve.

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
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The committee believes that the geoengineering community faces at once a challenge and an opportunity to participate and lead in initiatives that can reconcile the often conflicting demands of GES. Efforts are needed to understand these complex systems and successfully manage human interaction with Earth’s environment.

4.4 GEOENGINEERING FOR AN EARTH SYSTEMS INITIATIVE

The Geotechnical and Geohazards Program in the National Science Foundation (NSF) is advantageously positioned to play a major role in developing a major initiative in ESE with a large component for GES. An ESE or GES initiative should reflect the breadth of the issues involved and

  • encompass efforts from the nano- and microscale behavior of geomaterials to the global scale;

  • include data collection, management, interpretation, analysis, and visualization;

  • include the development of geosystems models, place-specific mesoscale investigations (Harte et al., 2001), and models to support policy decisions and adaptive management of environmental problems.

A GES initiative should also help define the design equations and approaches for Earth systems and their interactions in an effort to develop systematic new approaches to these problems. These points are discussed below.

4.4.1 The Scope of a GES Initiative

It is not possible to list every problem that could be included in a GES initiative, but it is possible to describe the scope generally and to point to a few important areas. A GES initiative should include any

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×

research problem that (1) involves geotechnology, and (2) has Earth system implications or exists in an Earth system context. In this regard, Earth systems have components that depend on each other (i.e., the outcome of one part of the problem affects the process in another part of the problem). There are feedback loops and perhaps dynamical interactions. The parts of an Earth system come from the biosphere (all life on Earth), geosphere (the rocks, soil, water, and atmosphere of Earth) and anthrosphere (political, economic, and social systems) as well as individual components in these spheres.

ESE problems are large in scope, have long-term consequences, and are clearly appropriate subjects for research. However, beyond the issues discussed below, NSF should be open to proposals that identify additional ESE issues.

The first problem is energy. Over the last hundred years, population growth and industrialization, coupled with the availability of inexpensive fossil fuel has increased the concentration of carbon dioxide in the atmosphere by nearly 30 percent. Global climate change is occurring and there is a consistent interpretation that the magnitude of the change cannot be explained without including anthropogenic effects (Mitchell et al., 2001; Santer et al., 2003, 2004). Figure 4.1 shows the carbon dioxide concentrations over the last 100 years compared to the mean temperature of Earth.

Two distinct energy problems must be solved. First, we have the legacy of the last 100 years of energy use. Second, we have to reach a future where emission-free energy is available in sufficient quantity to allow the work of the world’s economies to be done. Both these imperatives are Earth system problems with important geoengineering components.

The legacy problem includes dealing with the effects of greenhouse gases that are currently in our atmosphere and will remain on the order of 100 years, even if we could stop producing greenhouse gas emissions today (IPCC, 2001). Some key areas with geoengineering components will include

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×

FIGURE 4.1 Increased CO2 emissions causing a rise in atmospheric CO2 associated with a rise in global temperature (SOURCES: CO2 data from Ethridge et al. (2001) and Keeling and Whorf (2002). Temperature data from Jones et al. (1998) and Peterson and Vose (1997). Image from DOE, 2003a.

  • Carbon sequestration: Can we find ways to inject CO2 in the underground safely and economically and in sufficient quantities to make a difference? (Ten gigatons per year must be sequestered to stop emissions with the current energy-use pattern [see Caldeira et al., 2003].)

  • Water supply: Extreme weather patterns due to climate change are stressing an already stressed water supply problem in the world. Large populations exist where water supplies are low and water tables are dropping. Creative water conservation methods need to be developed (e.g., soil modification to reduce irrigation demand). Aquifer management is critical as well.

  • Natural hazard mitigation, particularly in urban environments: Extreme weather patterns also result from climate change and create greater hazards from flooding and landslides.

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×

The future supply of emission-free energy is a grand challenge that is perhaps the ultimate systems problem. Solar radiation, Earth’s geothermal capacity, and tidal energy theoretically provide many times more energy than will be needed in the next 100 years (http://smalley.rice.edu and Caldeira et al., 2003). However, the use of these energy sources is not now economical. Policy and economics will play a huge role in transitioning to an emission-free energy portfolio. Geoengineering will have a role in making these technologies more ubiquitously and economically available while not creating any new environmental problems. Geothermal energy is perhaps the best example of a geoengineering problem where the issues include finding new, hidden geothermal reservoirs with sufficient heat and fluid to be produced. The grand challenge, however, will be to find a way to use geothermal energy when the heat is present and when water or steam are not present to transfer the energy to the surface (called Enhanced Geothermal Systems). Geoengineering also has a role in the siting of wind farms, the use of tidal energy, and the appropriate use of hydropower.

A second problem with geoengineering aspects is dealing with the growth of megacities. Megacities are responsible for the largest anthropogenic affects on Earth. Heat and pollution generated by cities change the weather and draw resources (materials, air, water, and energy) from the rest of the world (Bugliarello, 1999, 2000, 2003). Risks from natural hazards are exacerbated in cities. Floods, earthquakes, volcanic eruption, and landslides all have magnified risk in areas of human concentration. The requirements for infrastructure to handle sanitation, energy, water, and transportation needs new creativity, particularly in the developing world. Beyond basic needs, cities will need to be livable spaces that are intelligently planned and agreeable to be in. These problems are not isolated engineering problems. The social, economic, and environmental aspects are daunting.

A third problem is a cross-cutting problem first clearly articulated by C. P. Snow in The Two Cultures (1959). If we are to succeed in ESE, the sciences and engineering will need to successfully interact with the social and political worlds. The implementation of any grand schemes to

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×

sequester carbon or manage the weather cannot even be conceived of without interaction and approval by society. It may well be that the economic and policy aspects of the energy problem dominate the technical problems. As Snow pointed out, these cultures do not communicate easily. NSF could address this issue directly by sponsoring institutes and workshops or by funding social scientists and physical scientists to work together.

An ESE program clearly would include biogeotechnology and we have seen in Chapter 3 a clear role for geoengineering in using biotechnology. If we are to release new bioengineered organisms to remediate waste or secure foundations, there will be significant systems implications requiring attention. What biogeoengineered systems are possible? How can we design biogeoengineering systems and how can we ensure their safety and develop social acceptability for their use? These are highly appropriate topics for a GES initiative.

The sustainability of human life on Earth is strongly affected by the sustainability of life in the developing world, which is home to most of humankind. The developing world’s burgeoning population also requires and desires significant improvements in their standards of living. A GES initiative should include research to develop solutions to natural hazards, environmental degradation, energy, sanitation, water supply, and transportation problems in the developing world. These solutions will also have to be environmentally acceptable and economically possible.

These GES imperatives are not all-inclusive, but they do give an idea of the critical importance of the ESE issues that will involve geoengineering. There are many important problems involving geoengineering that affect sustainability.

4.4.2 Material Behavior and Data Compilation and Interpretation Methods

Cross-cutting the topical areas discussed above, a GES initiative should encompass efforts from the nano- and microscale behavior of geomaterials to the global scale; data collection, interpretation, analysis, and visualization; and the development of geosystem models, place-

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×

specific mesoscale investigations and models to support policy decisions and adaptive management of environmental problems.

To understand complex interactions between geomaterials and the environment and to develop efficient and effective methods to manage and control these interactions, an improved understanding of nano- and microscale behavior of soil and rock masses is required. These interactions include geochemical and biological phenomena. In fact, the committee perceives the investigation of biological interactions with soil and rock for the purpose of modification and control to be an important component of GES, with potential applications in both developed countries for infrastructure construction and rehabilitation and in the developing world as cost-effective appropriate technologies.

Enormous amounts of geographically referenced data, including geological, geotechnical, and hydrological data, will be required to understand the spatial and temporal changes of Earth systems. The GES initiative should fund research to develop databases and data models and associated applications to support meso-, macro-, and global-scale Earth systems analysis and to collect data to populate the databases.

In terms of data collection and management, a number of federal agencies are already managing components of the systems. For example, the National Aeronautics and Space Administration (NASA) and National Oceanic and Atmospheric Administration (NOAA) collect important remote sensing data that bear on integrated monitoring of a large number of Earth processes. The Department of the Interior (DOI), Department of Energy (DOE), and the Department of Agriculture (USDA) include several agencies that have primary responsibility for Earth resources (e.g., the U.S. Geological Survey, Bureau of Land Management, Fish and Wildlife Service of the U.S. National Park Service, Office of Fossil Energy of the Department of Energy, and U.S. Forest Service). Collaboration between these federal agencies in developing systems analysis approaches to geoengineering could include the following actions:

  • Development of a roundtable to facilitate coordination;

  • Cooperative agreements to share and jointly archive information

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×

for pertinent databases, which should be extended to private developers as much as possible;

  • Integration and coordination of data collection efforts; and

  • Collaboration to develop tools specifically tailored toward ESE data needs (NASA, NOAA, Council of Europe, U.S. Bureau of Reclamation, USDA, Federal Highway Administration, DOE, and Department of Defense (DOD), including the Army Corps of Engineers).

Such coordination creates the possibility that other disciplines may join in addressing the challenges of GES, and that geoengineers will be leaders in defining the challenges not only of GES but also of many aspects of the emerging metadiscipline of ESE as well.

Modeling will play a major role in all aspects of GES. A GES initiative should include the development of systems analysis models for the problems encountered in geoengineering. The definition of the relevant Earth systems and how they interact is itself a research question. Which system components interact and how? Investigators should be encouraged to develop engineering models that recognize the hierarchy of interactions of the various components under different engineering design choices that can and should influence policy choices. This hierarchy must ultimately incorporate systems models at process, urban, regional, and global scales. These models could encompass civil infrastructure, transportation, energy and environment, mineral and water resources, air quality, climate change, waste management, and sociological and economic factors, as well as national security and defense. They could include aspects of the environment as simple as the migration and dimensions of sand dunes advancing on agricultural lands or as complex as the interaction of global carbon cycles, energy-use patterns, and climate. They will require substantial data collection, management, and processing and must include the incorporation of uncertainty.

It is likely that one of the more fruitful approaches to modeling human interaction with the environment will be on the mesoscale, that

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×

is, at a particular location where complexity is present and yet when small-scale phenomena can be identified and characterized, where the boundaries of the system are known and where hypotheses about the mesoscale behavior can be tested.

One of the critical tools for geoengineering will be a hierarchy of models that calculate the interactions of the various components under different policy and engineering design choices. These models will aspire to predict the behavior of the complex, interacting system components. Entirely new types of modeling that emphasize the interaction without losing fidelity in representing the components may be required. Models of dynamical systems, chaotic behavior, and emergent phenomena certainly have a role.

4.4.3 GES Design Approaches and Management Methods

The essence of engineering as opposed to science is the focus on design and management. In this light, the focus of an ESE or GES initiative is the eventual production of design approaches and management paradigms that address highly interactive Earth systems where anthropogenic effects play a dominant role and where the overall objective is sustainability. ESE presents a scope and complexity that has never before been addressed by engineers. In some cases, we may be able to extrapolate and modify engineering methods of the past. However, there is no accepted—or even tried—engineering methodology for problems as complex as global change. In fact, Allenby conjectured that ESE will not even be engineering in the usual sense in that it will be less management per se and more purposeful decision making (Personal communication from Brad Allenby to the committee, September 2003). The requirement for social and economic acceptability to this purposeful decision making about Earth will be profound. Many engineering projects have faced and solved what are considered the constraints imposed by the environment and social concerns with varying success. Case studies will show a wide variety of successes and failures in this regard. However, much more

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×

remains to be done to learn how to include and, as much as possible, formalize social concerns in design and to make the triple bottom line (economic, environmental, and social) the normative goal.

One of the most important geoengineering approaches to Earth systems analysis and design will be adaptive management (see Sidebar 4.4). For example, one of the largest current GES projects in the world is the rehabilitation of the Everglades. Adaptive management is a large part of this program (NRC, 2003d). In adaptive management, mitigation is designed, the outcome predicted, and then the outcome following a specific action is measured. Once the measurements are in hand, the predictions are compared to the measurement in order to determine if the engineering approach should be modified. This is philosophically much easier to describe than it is to do. In practice, it is extremely hard to know what to predict, what to measure, and how to compare these two types of quantities. NSF should invest in research to develop the techniques for integrating measurements with model predictions for adaptive management to update Earth systems models, especially for urban, regional, and global applications. This research should include the development of sustainability indicators and the use of these in evaluating the effect of engineering measures.

4.5 SUMMARY

If Chapter 3 presented an exciting vision for a new way to tackle geoengineering problems, this chapter has put those problems in a new global systems context. This new context will force geoengineers to think and act differently and to approach their work as part of a system that has social, environmental, and economic components. Geoengineers clearly have a crucial role in sustainability and ESE, which NSF, universities, and industry can begin to foster. The institutional needs required by the vision presented in Chapters 3 and 4 are described in Chapter 5.

Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×
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×
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×
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×
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×
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×
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×
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×
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×
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×
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×
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×
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Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×
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Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×
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Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×
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×
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Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×
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Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×
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Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×
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Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×
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Suggested Citation:"4 Geoengineering for Earth Systems and Sustainability." National Research Council. 2006. Geological and Geotechnical Engineering in the New Millennium: Opportunities for Research and Technological Innovation. Washington, DC: The National Academies Press. doi: 10.17226/11558.
×
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×
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The field of geoengineering is at a crossroads where the path to high-tech solutions meets the path to expanding applications of geotechnology. In this report, the term "geoengineering" includes all types of engineering that deal with Earth materials, such as geotechnical engineering, geological engineering, hydrological engineering, and Earth-related parts of petroleum engineering and mining engineering. The rapid expansion of nanotechnology, biotechnology, and information technology begs the question of how these new approaches might come to play in developing better solutions for geotechnological problems.

This report presents a vision for the future of geotechnology aimed at National Science Foundation (NSF) program managers, the geological and geotechnical engineering community as a whole, and other interested parties, including Congress, federal and state agencies, industry, academia, and other stakeholders in geoengineering research. Some of the ideas may be close to reality whereas others may turn out to be elusive, but they all present possibilities to strive for and potential goals for the future. Geoengineers are poised to expand their roles and lead in finding solutions for modern Earth systems problems, such as global change, emissions-free energy supply, global water supply, and urban systems.

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